best Scrubs guest stars.

Fox's brilliance aside, his presence made the production process challenging for an interesting reason. While Fox's Parkinson's diagnosis in 1991 gradually made it more difficult for him to continue acting, it wasn't his condition that caused the Scrubs season 3 issue in question. Instead, the challenge was faced by the writers of Fox's Scrubs episodes, but there are far worse problems to have than the one that had to be solved in this instance.

Michael J Fox's Scrubs Episodes Had To Accommodate The Cast's Demand To Work With Him

Fox's story had to find room for plenty of collaboration with the Scrubs cast

Speaking with CBS around the time of Michael J. Fox's Scrubs debut in 2005, showrunner Bill Lawrence (who also co-created Spin City, starring Fox) revealed one of the biggest problems the writers had to for. In short, the Scrubs cast was so excited to have Fox on the show that they all wanted to be part of Dr. Kevin Casey's two-episode arc. With a combined runtime of around 40 minutes, there wasn't much space to accommodate this desire, but Scrubs somehow managed to pull it off.

"The hardest part, Lawrence said, was writing a script that allowed eager cast a chance to work opposite Fox." - Lynn Elber, CBS.

As is often the case with Scrubs, Zach Braff's Dr. John "JD" Dorian had what was arguably the main arc with Fox's character. However, other characters, like Sarah Chalke's Elliot Reid and John C. McGinley's Dr. Cox, still had substantial storylines with Dr. Kevin Casey. So, despite the challenge of making sure all the main of the Scrubs cast were content with their shared Michael J. Fox screen time, it would seem the obstacle wasn't insurmountable.

Dr. Casey's OCD Helped Michael J. Fox Return To Acting

The symptoms of Fox's Scrubs character allowed him to perform more freely

After Spin City ended in 2001, Michael J. Fox's took mainly voice roles until he was cast in Scrubs. Speaking with Culture, Fox has discussed how his Scrubs character's struggles with OCD allowed the actor to reframe how he viewed his own diagnosis of Parkinson's Disease. Using his time on Family Ties as a reference, Michael J. Fox suggested acting on Scrubs was a much more traditional acting challenge, as instead of having to quell the tremors brought on by his condition, he could fold them into his performance as Dr. Kevin Casey.

“I discovered that I could focus less on the externals and stop trying to hide my symptoms. This was in stark relief from my days on Spin City, when I’d keep a live audience waiting while I paced my dressing room, pounding my arm with my fist in a vain attempt to quell the tremors. On Scrubs, instead of trying to kill it, I invited my Parkinson’s with me to the set. I felt free to concentrate on the task that any actor, able-bodied or not, is charged with accomplishing: uncovering the internal life of another human being. Putting the emphasis on my character’s vulnerabilities and not my own, Parkinson’s could in fact disappear.”

After Scrubs, Michael J. Fox went on to star in a number of other TV shows. One of which, the eponymously named Michael J. Fox show, even had the star's character suffering from the same condition as the actor playing him. It's unclear to what extent Fox's time as Dr. Casey influenced his future characters, but it's possible the actor's Scrubs character served as a solid foundation for the rest of his career. In 2020, Fox officially announced his retirement from acting.

Why Michael J. Fox Was One Of Scrubs' Best Guest Stars

Dr. Kevin Casey had one of the best mini-arcs in Scrubs

Scrubs ended its run with an impressive list of guest stars such as Matthew Perry, Brendan Fraser, Courtney Cox, and Ryan Reynolds. Of all the Scrubs guest stars, Fox is easily one of the best, if not already sitting at the number one spot. Despite having a sitcom background, Scrubs allowed him to explore a deeply emotional storyline that served as an allegory for the daily battles fought by him and so many others. In addition, he also stuck the landing on all of his comedic moments, and striking that balance is essential for a show like Scrubs​​​​​.

With Fox being such a likable personality, it's also incredibly rewarding to hear that his two Scrubs episodes as Dr. Kevin Casey appear to have been very therapeutic for the actor behind the character, as well as knowing the role was something of a resurgence in Fox's belief that he could continue to act. Of course, it's not possible to know this piece of behind-the-scenes trivia without reading the comments from Fox himself, but it all still adds to the reason and the story behind how and why Michael J. Fox became such a beloved Scrubs guest star.

Sources: CBS, Culture